Hollow auger



S. P. GILBERT, 0F RACINE, VISCONSIN.

HOLLOW AUGER.

Specication of .Letters Patent No. 31,883, dated April 2, 1861.

To all whom it may concern:

Be it known `that I, S. P. GILBERT, of Racine, in the county of Racine and State of IVisconsin, vhave invented a new and useful Improvement in Tubular Augers; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making a part of this specification, in which- Figure l represents a plan view of a machine constructed to bore wooden pipes. Fig. 2 is a longitudinal vertical section taken through the machine of Fig. l.

Similar letters of reference indicate corresponding parts in both figures.

To enable those skilled in the art to make and use my invention, I will proceed to describe its construction and operation.

A is a suitable frame upon which the auger, the machinery for operating it, and the logs to be bored are supported. On one end of this frame A are suitable guide ways for the log blocks B B, which blocks are secured to a carriage B which can be moved in a direction 'with the length of the log B2 either back or forth by means of a rack and pinion as shown in Fig. 2 of the drawings or by any other suitable means. The log blocks B B may be made perpendicularly adjustable so that the axis of the log may be brought in a line with the axis of the auger. The journal boxes b b support the rear end of a cylindrical case C and the journal boxes CZ, CZ support the rear end of a tube G which tube Gr extends out behind the rear end of cylindrical case C.

D is the cutter or bit secured to the front end of the tube G and rotated thereby.

The cylindrical case C, central tube G and bit D form my improved auger or implement. j

Between the journal boxes o b is a belt wheel F which gives a rotary motion to the case C in one direction while the belt wheel e between boxes CZ CZ gives rotary mot-ion to the tubeG in an opposite direction to that of the case C. The wheels F and e are rotated by bands which communicate with a driving shaft I-I; one of the bands is crossed and this is what transmits a rightand left rotary motion to the case C and tube G from one shaft.

E is a `sliding block which projects up from frame A between the carriage B and the boxes b, b and supports the tubes C and G keeping them steady and well directed to the work. This block E may be attached to the carriage B so as tomoverwith it or y it may be moved by hand, or in any convenient way. IThe block E should have a steady and lirm support on frame A and the case C should be allowed to turn freely in the journal box in this block, E.

The bit D is somewhat larger in its diameter than the case C over the end of which it slips; and the bit has a central short tube g over which the end of tube Gr fits as shown in Fig. 2. The end of bit D is furnished with cutting lips like any bit of this description which perform the cutting and discharge the chips through the bit between the outside of the tube G and the case C and these chips are received by a screw thread or worm c which is formed around the out side of tube G. By this worm the chips are carried back and discharged from the rear end of case C as represented in red lines Fig. 2.

The cylindrical bit D does not cut to its center but it leaves a solid core c which, as

the boring progresses passes through the tubular carrier Gr as shown in Fig. 2 while the chips pass on the outside of the tube between the case and the tube. The short central tube g of bit D is smaller in its diameter than the inside of tube G into the end of which it fits so that the core a will not touch the sides of the tube G and cause friction, as this` core is smaller than the bore of this tube. This is also the case with the bit D and case C, the former being larger than the latter the case C will not touch the sides of the hole l in the log providing that the implement is guided straight through the center of the log.

The operation of the entire machine is as follows: The log is properly set and adjusted on its blocks B, B so that the axis of the log will be in a line with the axis of the tube Gr and the case C, which are concentric. The tube Gr and case C are now rotated in opposite directions. The bearing block E is adjusted so that the end of case C is steadied and the end of the log is then advanced to the work by turning the crank 7L which is on the pinion shaft z'. As the work of boring progresses the carriage will push the bearing block E along, which block steadies and supports the case C ina true center with the log. It will thus be seen that the central tube G is supported at both of its ends. It

Will also be seen that the case C is supported at both ends, at one end in its journal boxes b b and at the other end in its travelingsupport E. The boring of very long logs may thus be accomplished With lmy machine with comparatively little friction and in the most accurate manner. If no exterior case Were employed it Would be difficult to guide the auger properly, because the edges of the spiral Worm can give no suitable support for that purpose. But by employing a rotary case the implement may be set and guided so as to bore with perfect accuracy, no matter what the character of the Wood to Which it is applied; and the chips Will also be more easily and freely discharged as the Work progresses.

I d0 not claim the invention of a hollow boring cylinder, which leaves no core, as patented by VVycko?. Nor do I claimthe invention of a hollow core forming augeigvas patented by Stevens. But Y Havingdescribed my invention what I claim 'and desire to secure by Letters Patent is- The combination with the bit D and hollow auger G of the rotary case C, substantially as and for the purposes herein shown and described.

s. P. GILBERT.

lVitnesses E. E. GILBERT, L. H. FELLoWs. 

